It's difficult to memorize the Hyakunin Isshu.

He is studying the history of African Americans.

They have a variety of opinions, making it difficult to agree.

He is recognized as the top person in that field.

She is suffering from Eating Disorder Not Otherwise Specified.

World War II lasted from 1939 to 1945.

This is the second time he's been late. Well, they say what happens twice will happen three times.

This regular dodecahedron is a geometric shape with perfect symmetry.

This solid is called a regular icosahedron, and it is made up of 20 equilateral triangles.

Zoonosis is a disease that spreads from animals to humans, or vice versa.